Dear colleagues,
we have a post thyroidectomy patient who is now taking 225ug of thyroxine daily but her Free T4 remains <5.2pmol/L and her TSH is 75U/L. (Abbott architect methods). Her Free T3 is also low at 2.3pmol/L (2.6-5.7).
She is clinically hypothyroid, which makes heterophilic ab interference unlikely, and we are confident that she is complying with treatment and has no GI pathology that could cause absorption problems.
Prior to thyroidectomy for Grave's disease ( in Oct 2006), she was rendered euthyroid with carbimazole, steroids, lithium and iodine.
Her current medication, besides thyroxine, is predisolone (5mg/day), risedronate, folic acid and calcichew-D3.
Could anyone suggest why she is not responding to the thyroxine?
Best wishes
Ian Barlow
Scunthorpe
UK